The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction ...The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse actuator.The impact point easily deviates from the target,and thus the correction result cannot be readily evaluated.However,the cost of shooting tests is considerably high to conduct many tests for data collection.To address this issue,this study proposes an aiming method for shooting tests based on small sample size.The proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion center.The experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future.展开更多
Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also ...Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also need to modulate the lateral force or trajectory (perpendicular to the vertical plane of fire direction). Therefore, the structure of control cabin of two-dimensional trajectory correction projectile (TDTCP) is more complicated than that of one-dimensional trajectory correction projectile (ODTCP). To simplify the structure of control cabin of TDTCP and reduce the cost, a scheme of adding a damping disk to the control cabin of ODTCP has been developed recently. The damping disk is unfolded at the right moment during its flight to change the ballistic drift of spin stabilized projectile. For this technical scheme of TDTCP, a fast and accurate impact point prediction method based on extended Kalman filter is presented. An approximate formula for predicting the ballistic drift and trajectory correction quantity is deduced. And the lateral correction capability for different fire angles and its influencing factors are analyzed. All the work is valuable for further research.展开更多
The two-dimensional trajectory correction needs to adjust not only the force in velocity direction,but also the lateral force or lateral trajectory (normal to the perpendicular plane of fire direction) . Therefore,its...The two-dimensional trajectory correction needs to adjust not only the force in velocity direction,but also the lateral force or lateral trajectory (normal to the perpendicular plane of fire direction) . Therefore,its structure of control cabin is more complicated than that of one-dimensional trajectory correction projectiles (ODTCP). In order to simplify the structure and reduce the cost,a scheme of adding a damping disc to the control cabin of ODTCP has been developed recently. The damping disc will unfold at the right moment during its flight to change the ballistic drift of rotary projectiles. Aimed at this technical scheme,a mathematical model of two-dimensional trajectory corrections was discussed according to the theory of exterior ballistics. An approximate formula for predicting the ballistic drift and trajectory correction was deduced. The capability of lateral trajectory correction and the flight stability of TDTCP were also analyzed. All the work is valuable for further research.展开更多
The optimization method of the canard trajectory correction fuze's controlled trajectory phase is researched by using the aerodynamics of aerocraft and the optimal control theory, the trajectory parameters of the ...The optimization method of the canard trajectory correction fuze's controlled trajectory phase is researched by using the aerodynamics of aerocraft and the optimal control theory, the trajectory parameters of the controlled trajectory phase based on the least energy cost are determined. On the basis of determining the control starting point and the target point, the optimal trajectory and the variation rule of the normal overload with the least energy cost are provided, when there is no time restriction in the simulation process. The results provide a theoretical basis for the structure design of the canard mechanism.展开更多
This paper presents an actuator used for the trajectory correction fuze,which is subject to high impact loadings during launch.A simulation method is carried out to obtain the peak-peak stress value of each component,...This paper presents an actuator used for the trajectory correction fuze,which is subject to high impact loadings during launch.A simulation method is carried out to obtain the peak-peak stress value of each component,from which the ball bearings are possible failures according to the results.Subsequently,three schemes against impact loadings,full-element deep groove ball bearing and integrated raceway,needle roller thrust bearing assembly,and gaskets are utilized for redesigning the actuator to effectively reduce the bearings’stress.However,multi-objectives optimization still needs to be conducted for the gaskets to decrease the stress value further to the yield stress.Four gasket’s structure parameters and three bearings’peak-peak stress are served as the four optimization variables and three objectives,respectively.Optimized Latin hypercube design is used for generating sample points,and Kriging model selected according to estimation result can establish the relationship between the variables and objectives,representing the simulation which is time-consuming.Accordingly,two optimization algorithms work out the Pareto solutions,from which the best solutions are selected,and verified by the simulation to determine the gaskets optimized structure parameters.It can be concluded that the simulation and optimization method based on these components is effective and efficient.展开更多
A control system for correction mechanisms through the whole trajectory is proposed based on the principle of one-dimensional trajectory correction projectile. Digital signal processing( DSP) is utilized as the core c...A control system for correction mechanisms through the whole trajectory is proposed based on the principle of one-dimensional trajectory correction projectile. Digital signal processing( DSP) is utilized as the core controller and gobal positioning system( GPS) is used to measure trajectory parameters to meet the requirements of calculating ballistics and system functions. Firstly,the hardware,mainly including communication module,ballistic calculation module,boosting& detonating module and data storage module,is designed. Secondly,the supporting software is developed based on the communication protocols of GPS and the workflow of control system. Finally,the feasibility and the reliability of the control system are verified through dynamic tests in a car and live firing experiments. The system lays a foundation for the research on trajectory correction projectile for the whole trajectory.展开更多
The research on multiple launch rocket system(MLRS)is now even more demanding in terms of reducing the time for dynamic calculations and improving the firing accuracy,keeping the cost as low as possible.This study emp...The research on multiple launch rocket system(MLRS)is now even more demanding in terms of reducing the time for dynamic calculations and improving the firing accuracy,keeping the cost as low as possible.This study employs multibody system transfer matrix method(MSTMM),to model MLRS.The use of this method provides effective and fast calculations of dynamic characteristics,initial disturbance and firing accuracy.Further,a new method of rapid extrapolation of ballistic trajectory of MLRS is proposed by using the position information of radar tests.That extrapolation point is then simulated and compared with the actual results,which demonstrates a good agreement.The closed?loop fire correction method is used to improve the firing accuracy of MLRS at low cost.展开更多
A prototype of impulse thruster for radial thrust trajectory correction munitions is designed. It adopts semiconductor bridge (SCB) as ignition element,Ti/KClO4 (TK) as ignition charge and ammonium perchlorate/alumini...A prototype of impulse thruster for radial thrust trajectory correction munitions is designed. It adopts semiconductor bridge (SCB) as ignition element,Ti/KClO4 (TK) as ignition charge and ammonium perchlorate/aluminium (NA) or potassium picate/RDX (KR) as main charge. A thrust test device of impulse thruster is also designed. The output performance of the impulse thruster prototype is tested by the device. The tested results show that it can meet the safety requirements of 1A1W/5 min no-fire level and produce 0.2-0.6 N·s thrust impulse within 3ms of action time under certain test conditions; the corresponding ignition delay time is less than 0.5 ms.展开更多
The system composition, the operational principle of terminal correction mortar projectiles （TCMP） and the concept planning design of TCMP are researched in this paper. An overall design and aerodynamic configuratio...The system composition, the operational principle of terminal correction mortar projectiles （TCMP） and the concept planning design of TCMP are researched in this paper. An overall design and aerodynamic configuration layout for TCMP are made in this paper, and its aerodynamic coefficients are calculated by using computational fluid dynamics （CFD） software. Test results of TCMP simulated ballistic projectiles indicate the designed TCMP can satisfy the interior ballistic demand and has a fine flight stability. The drag coefficients identified from the radar velocity-time data are in accord with the CFD computed results. According to the exposure frequency of the ground laser designator, a four-quadrant impulse correction scheme and a high exposure frequency impulse correction scheme are brought. The latter can calculate the target azimuth angle by counting the times of the facula passing through one quadrant. Simulation results also show that the guidance precision of the velocity pursuit is higher than that of the body pursuit, and the detector axis is less circuitous. Researches on the typical trajectory indicate that the terminal impulse correction can improve the hit precision of TCMP remarkably.展开更多
基金the National Natural Science Foundation of China(Grant No.61973033)Preliminary Research of Equipment(Grant No.9090102010305)for funding the experiments。
文摘The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse actuator.The impact point easily deviates from the target,and thus the correction result cannot be readily evaluated.However,the cost of shooting tests is considerably high to conduct many tests for data collection.To address this issue,this study proposes an aiming method for shooting tests based on small sample size.The proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion center.The experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future.
文摘Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also need to modulate the lateral force or trajectory (perpendicular to the vertical plane of fire direction). Therefore, the structure of control cabin of two-dimensional trajectory correction projectile (TDTCP) is more complicated than that of one-dimensional trajectory correction projectile (ODTCP). To simplify the structure of control cabin of TDTCP and reduce the cost, a scheme of adding a damping disk to the control cabin of ODTCP has been developed recently. The damping disk is unfolded at the right moment during its flight to change the ballistic drift of spin stabilized projectile. For this technical scheme of TDTCP, a fast and accurate impact point prediction method based on extended Kalman filter is presented. An approximate formula for predicting the ballistic drift and trajectory correction quantity is deduced. And the lateral correction capability for different fire angles and its influencing factors are analyzed. All the work is valuable for further research.
文摘The two-dimensional trajectory correction needs to adjust not only the force in velocity direction,but also the lateral force or lateral trajectory (normal to the perpendicular plane of fire direction) . Therefore,its structure of control cabin is more complicated than that of one-dimensional trajectory correction projectiles (ODTCP). In order to simplify the structure and reduce the cost,a scheme of adding a damping disc to the control cabin of ODTCP has been developed recently. The damping disc will unfold at the right moment during its flight to change the ballistic drift of rotary projectiles. Aimed at this technical scheme,a mathematical model of two-dimensional trajectory corrections was discussed according to the theory of exterior ballistics. An approximate formula for predicting the ballistic drift and trajectory correction was deduced. The capability of lateral trajectory correction and the flight stability of TDTCP were also analyzed. All the work is valuable for further research.
文摘The optimization method of the canard trajectory correction fuze's controlled trajectory phase is researched by using the aerodynamics of aerocraft and the optimal control theory, the trajectory parameters of the controlled trajectory phase based on the least energy cost are determined. On the basis of determining the control starting point and the target point, the optimal trajectory and the variation rule of the normal overload with the least energy cost are provided, when there is no time restriction in the simulation process. The results provide a theoretical basis for the structure design of the canard mechanism.
基金The authors would like to acknowledge National Defense Pre-Research Foundation of China(Grant No.41419030102)to provide fund for conducting experiments.
文摘This paper presents an actuator used for the trajectory correction fuze,which is subject to high impact loadings during launch.A simulation method is carried out to obtain the peak-peak stress value of each component,from which the ball bearings are possible failures according to the results.Subsequently,three schemes against impact loadings,full-element deep groove ball bearing and integrated raceway,needle roller thrust bearing assembly,and gaskets are utilized for redesigning the actuator to effectively reduce the bearings’stress.However,multi-objectives optimization still needs to be conducted for the gaskets to decrease the stress value further to the yield stress.Four gasket’s structure parameters and three bearings’peak-peak stress are served as the four optimization variables and three objectives,respectively.Optimized Latin hypercube design is used for generating sample points,and Kriging model selected according to estimation result can establish the relationship between the variables and objectives,representing the simulation which is time-consuming.Accordingly,two optimization algorithms work out the Pareto solutions,from which the best solutions are selected,and verified by the simulation to determine the gaskets optimized structure parameters.It can be concluded that the simulation and optimization method based on these components is effective and efficient.
文摘A control system for correction mechanisms through the whole trajectory is proposed based on the principle of one-dimensional trajectory correction projectile. Digital signal processing( DSP) is utilized as the core controller and gobal positioning system( GPS) is used to measure trajectory parameters to meet the requirements of calculating ballistics and system functions. Firstly,the hardware,mainly including communication module,ballistic calculation module,boosting& detonating module and data storage module,is designed. Secondly,the supporting software is developed based on the communication protocols of GPS and the workflow of control system. Finally,the feasibility and the reliability of the control system are verified through dynamic tests in a car and live firing experiments. The system lays a foundation for the research on trajectory correction projectile for the whole trajectory.
基金supported by the Na- tional Natural Science Foundation of China (No. 11472135)the Science Challenge Project (No. JCKY2016212A506- 0104)
文摘The research on multiple launch rocket system(MLRS)is now even more demanding in terms of reducing the time for dynamic calculations and improving the firing accuracy,keeping the cost as low as possible.This study employs multibody system transfer matrix method(MSTMM),to model MLRS.The use of this method provides effective and fast calculations of dynamic characteristics,initial disturbance and firing accuracy.Further,a new method of rapid extrapolation of ballistic trajectory of MLRS is proposed by using the position information of radar tests.That extrapolation point is then simulated and compared with the actual results,which demonstrates a good agreement.The closed?loop fire correction method is used to improve the firing accuracy of MLRS at low cost.
基金the Ministerial Level Advanced Research Foundation (51305080302)
文摘A prototype of impulse thruster for radial thrust trajectory correction munitions is designed. It adopts semiconductor bridge (SCB) as ignition element,Ti/KClO4 (TK) as ignition charge and ammonium perchlorate/aluminium (NA) or potassium picate/RDX (KR) as main charge. A thrust test device of impulse thruster is also designed. The output performance of the impulse thruster prototype is tested by the device. The tested results show that it can meet the safety requirements of 1A1W/5 min no-fire level and produce 0.2-0.6 N·s thrust impulse within 3ms of action time under certain test conditions; the corresponding ignition delay time is less than 0.5 ms.
基金the Ministerial Level Advanced Research Foundation (40406030101)
文摘The system composition, the operational principle of terminal correction mortar projectiles （TCMP） and the concept planning design of TCMP are researched in this paper. An overall design and aerodynamic configuration layout for TCMP are made in this paper, and its aerodynamic coefficients are calculated by using computational fluid dynamics （CFD） software. Test results of TCMP simulated ballistic projectiles indicate the designed TCMP can satisfy the interior ballistic demand and has a fine flight stability. The drag coefficients identified from the radar velocity-time data are in accord with the CFD computed results. According to the exposure frequency of the ground laser designator, a four-quadrant impulse correction scheme and a high exposure frequency impulse correction scheme are brought. The latter can calculate the target azimuth angle by counting the times of the facula passing through one quadrant. Simulation results also show that the guidance precision of the velocity pursuit is higher than that of the body pursuit, and the detector axis is less circuitous. Researches on the typical trajectory indicate that the terminal impulse correction can improve the hit precision of TCMP remarkably.
